E. coli cells are simultaneously infected with two strains of phage ). One strain has a mutant host range, is temperature sensitive, and produces clear plaques (genotype h st c); another strain carries the wildtype alleles (genotype h* st* c*). Progeny phages are collected from the lysed cells and are plated on bacteria. The following numbers of different progeny phages are obtained: Progeny phage genotype Number of plaques h* c* st* 321 h c st 338 h* c st 26 hc* st* 30 h* c st* 106 hc* st 110 h* c* st h c st* 6.
Q: Which of the following statements about Hfr strains of E. coli is FALSE? Group of answer choices…
A: The recipient cell remains recipient after the Hfr cell and F- cell cross. In this conjugation,…
Q: In the genotype presented (genomic plus plasmid genes), which of the following statements Is…
A: Lac operon codes Lac Z,Y,A genes which are structural genes encoding Beta galactosidase,Permease,…
Q: Austin Taylor and Edward Adelberg isolated some 200 new strains of Hfr cells that they then used to…
A: The transformation, transduction, and conjugation are the horizontal transfer mechanism through…
Q: Let’s suppose a new strain of P1 phage has been identified thatpackages larger pieces of the E. coli…
A: When two genes are present close to each other in a chromosome, the bacteriophages can package the…
Q: Based on the mode of action of aflatoxin (Figure 16-16),propose a scenario that explains its…
A: Aflatoxins are toxin or poisonous chemicals produced by molds such as Aspergillus flavus and…
Q: Sam is working in a genetics lab this summer to gain more hands-on experience before applying to…
A: DNA replication is necessary to ensure genetic continuity and genome inheritance from parents to…
Q: Two mutations that affect plaque morphology in phages (a and b ) have been isolated. Phages carrying…
A: Recombination frequency (θ) is the frequency with which a single chromosomal crossover will take…
Q: In your laboratory, you have an F − strain of E. coli that is resistant to streptomycin and is…
A: Conjugation is the transfer of genetic material from one bacterium to another bacterium. Here, a…
Q: As much fun as lInterrupted mating experiments are, they don't always capture a truly accurate…
A: From the given table it is observable that for the growth of P13 it is necessary to have a media…
Q: A donor strain of bacteria with alleles a+ b+ c+ is infected with phages to map the donor chromosome…
A: Bacteria are unicellular and prokaryotic organisms that live in wide variety of environments. It…
Q: Which of the following statements is not applicable to conjugation? A) OF factors are transferrable…
A: Bacteria are single-celled microbes. These organisms are capable of exchanging inheritable material…
Q: In recombination studies of the rII locus in phage T4, what is the significance of the value…
A: Seymour Benzer developed an experimental system around 1950s for analyzing various subparts of a…
Q: An Hfr strain that is leuA+ and thiL+ was mixed with a strain thatis leuA− and thiL−. In the data…
A: Transfer of genes in prokaryotes occurs through horizontal transfer mechanisms such as transduction,…
Q: Two mutations that affect plaque morphology in phages (a− and b −) have been isolated. Phages…
A: Plaque phenotype numbers are: a+ b+ 2043 a+ b- 320 a- b+ 357 a- b- 2134…
Q: A donor strain of bacteria with genotype leu+ gal− pro+ is infected with phages. The phage lysate…
A: The transduction is the process of transfer of genes of a genetic material from bacteria to the…
Q: By conducting conjugation experiments between Hfr and recipientstrains, Wollman and Jacob mapped the…
A: On the basis of the given information, it can easily be predicted that it explains the…
Q: An F' merozygote is formed as a result of the following events: 1) the recipient cell receives…
A: The inaccurately exercised plasmid from the chromosome of Hfr and causes the part of chromosomes (F…
Q: Beadle and Tatum Experiment X rays Conidia from the cultures that fail to grow on minimal medium are…
A: Beadle and Tatum experiment... Beadle and Tatum started their experiment by creating mutants of the…
Q: In order to determine the genetic material of a T2 phage, Alfred Hershey and Martha Chase conducted…
A: The proteins holding a more complex nature than DNA was thought to be the carried genetic…
Q: DNA containing the genes gin+ phe+ lys+ was used to transform bacterial cells of genotype gln- phe-…
A: As per the question :- Genotypes and number of individuals obtained are as:- A ) gly + phe+ lys +…
Q: Bacterial cells were coinfected with two types of bacteriophage lambda: One carried the c+ allele…
A: The bacteriophage is a type of virus that infects the bacterial cell. The bacteriophage is made up…
Q: Which conclusions are consistent with these data? Why? A) Strains A and B carry mutations in the…
A: Answer :- Option (C) is correct. - Strains B, C, and D carry mutations in the same gene.
Q: A donor strain of bacteria with alleles a* b* c* is infected with phages to map the donor chromosome…
A: Step 1 Introduction Transduction is a type of horizontal gene transfer (gene transfer between two…
Q: E. coli cells are simultaneously infected with two strains of phage λ. One strain has a mutant host…
A: A gene is a stretch of nucleotides present in the DNA molecule. It encodes information for the…
Q: In five Hfr strains, each of which was used to build a time-of-transfer map, the genes entered the…
A: F+ cells are those cells which contains the F plasmid. F- cells are those which do not contain F…
Q: By conducting conjugation experiments between Hfr and recipientstrains, Wollman and Jacob mapped the…
A: Transfer of genes in prokaryotes occurs through horizontal transfer mechanisms such as transduction,…
Q: Bradley did two test PCR experiments with his phage genomic DNA. For one experiment he used G…
A: For categorizing phages, the term 'clusters' is used for groups of similar phages. It aids in…
Q: A) Indicate the order of the point mutations in the rII region.
A:
Q: In Figure 5-5,a. Why do A− and B− cells, by themselves, not formcolonies on the plating medium?b.…
A: A gene is the essential physical and functional unit of heredity. They are comprised of DNA…
Q: When various strains of λ phage are seeded on a lawn of E. coli, they can form clear or turbid…
A: The Operon is the regulatory system present in DNA in cluster form, which contains structural genes…
Q: In step 2 (above) in the identification of the colony that contains a targeted gene, ____. a.…
A: The shown steps are the part of colony hybridization to identify a gene of interest. Colony…
Q: A donor strain of bacteria with genotype leu* gal pro* is infected with phages. The phage lysate…
A: The transduction is the process of transfer of genes of a genetic material from bacteria to the…
Q: Explain the role of the gene that is the selectable marker gene in this experiment.
A: Introduction In the RDT (recombinant DNA technology), we insert the segment of DNA into the vector…
Q: Imagine that you are a student in Alfred Hershey and Martha Chase’s lab in the late 1940s. You are…
A: Alfred Hershey and Martha Chase’s experiment result that the Dna is the genetic material and the…
Q: Most yeast grow suspended in culture, but some yeast grow as a film on the top of a liquid culture.…
A: Yeasts are unicellular eukaryotic organisms that are classified under the kingdom fungi. Yeasts are…
Q: You have conducted a transposon mutagenesis experiment using the same PRL27 system that was used…
A: Transposon mutagenesis, is a biological process that allows genes to be transferred to a host…
Q: Three pairs of bacterial cells with the given genotypes undergo conjugation. Place match the…
A: F+ bacteria contain gene for the formation of sex pillus which is important for the transfer of…
Q: T. Miyake and M. Demerec examined proline-requiring mutations in the bacterium Salmonella…
A: Transduction is the process by which a virus transfers genetic material from one bacterium to…
Q: 1. What are the basic requirements for the insertion of λ into the E. Coli genome? 2. What special…
A: Hi! Thanks for your question. As you have posted multiple questions, we are answering only the first…
Q: Nine rII− mutants of bacteriophage T4 were used inpairwise infections of E. coli K(λ) hosts. Six of…
A: Sudden heritable changes that occur in the nucleotide sequence of the genome of an organism…
Q: You identify a new bacterial species in the koi pond between the Curry Student Center and Robinson…
A: Bacteria are prokaryotic organisms. They do not have a true nucleus and no cellular organelles.…
Q: This is question 34, chapter 7, Hartwell Glenetics 6th textbook. I do not know how to answer parts b…
A: Sudden heritable changes that occur in sequence of an organism resulting in the production of an…
Q: By conducting conjugation experiments between Hfr and recipientstrains, Wollman and Jacob mapped the…
A: DNA is the genetic material in most living organisms. It is the information hub of the cell that…
Q: An F' cell with a functional copy of the threonine gene on the bacterial chromosome, but with a…
A: Introduction Conjugation is the transfer of genetic material from one bacterium to another through…
Q: Which of the following statements about conjugation is false? After a F- cell has conjugated…
A: Bacteria have the ability to respond to selective pressures and will start to adapt to new…
Q: In order to determine the genetic material of a T2 phage, Alfred Hershey and Martha Chase conducted…
A: Phosphorus and sulfur both are the elements that cycle through the biotic and abiotic parts of an…
Q: when various strains of lambda phage are seeded on a lawn of e.coli, they can form clear or turbid…
A: Bacteriophages are the viruses that infect and replicate within the bacterial host. They are of two…
Q: An Hfr strain that is leuA+ and thiL+ was mixed with a strain thatis leuA− and thiL−. In the data…
A: Auxotrophs are microbes designed to or naturally lack some enzymes to produce essential nutrients.…
Determine the coefficient of coincidence and the interference
Trending now
This is a popular solution!
Step by step
Solved in 2 steps with 2 images
- E. coli cells are simultaneously infected with two strains of phage λ. One strain has a mutant host range, is temperature sensitive, and produces clear plaques (genotype h st c); another strain carries the wildtype alleles (genotype h+ st+ c+). Progeny phages are collected from the lysed cells and are plated on bacteria. The following numbers of different progeny phages are obtained: Progeny phage genotype Number of plaques h+ c+ st+ 321 h c st 338 h+ c st 26 h c+ st+ 30 h+ c st+ 106 h c+ st 110 h+ c+ st 5 h c st+ 6 a. Determine the order of the three genes on the phage chromosome. b. Determine the map distances between the genes. c. Determine the coefficient of coincidence and the interferenceTwo mutations that affect plaque morphology in phages (a− and b −) have been isolated. Phages carrying both mutations (a− b−) are mixed with wild-type phages (a+ b+) and added to a culture of bacterial cells. Once the phages have infected and lysed the bacteria, samples of the phage lysate are collected and cultured on plated bacteria. The following numbers of plaques are observed: Plaque phenotype Number a+ b+ 2043 a+ b− 320 a− b+ 357 a− b− 2134 What is the frequency of recombination between the a and b genes?An ade+ arg+ cys+ his+ leu+ pro+ bacterial strain is knownto be lysogenic for a newly discovered phage, but the siteof the prophage is not known. The bacterial map isleucysarghisadeproThe lysogenic strain is used as a source of the phage, andthe phages are added to a bacterial strain of genotypeade- arg- cys- his- leu- pro-. After a short incubation,samples of these bacteria are plated on six differentmedia, with the supplementations indicated in thefollowing table. The table also shows whether colonieswere observed on the various media.PresenceMedium Ade Arg Cys His Leu Pro of colonies1 - + + + + + N2 + - + + + + N3 + + - + + + C4 + + + - + + N5 + + + + - + C6 + + + + + - NNutrient supplementation in medium(In this table, a plus sign indicates the presence of anutrient supplement, a minus sign indicates that asupplement is not present, N indicates no colonies, and Cindicates colonies present.)a. What genetic process is at work here?b. What is the approximate locus of the prophage?
- Nine rII− mutants of bacteriophage T4 were used inpairwise infections of E. coli K(λ) hosts. Six of themutations in these phages are point mutations; theother three are deletions. The ability of the doubly infected cells to produce progeny phages in large numbers is scored in the following chart.1 2 3 4 5 6 7 8 91 − − + + − − − + +2 − + + − − − + +3 − − + − + − −4 − + − + − −5 − − − + +6 − − − −7 − + +8 − −9 −The same nine mutants were then used in pairwise infections of E. coli B hosts. The production of progenyphages that can subsequently lyse E. coli K(λ) hosts isnow scored. In the table, 0 means the progeny do notproduce any plaques on E. coli K(λ) cells; − meansthat only a very few progeny phages produce plaques;and + means that many progeny produce plaques(more than 10 times as many as in the − cases).1 2 3 4 5 6 7 8 91 − + + + + − − + +2 − + + + + − + +3 0 − + 0 + + −4 − + − + + +5 − + − + +6 0 0 − +7 0 + +8 − +9 −a. Which of the mutants are the three deletions? Whatcriteria did…Two mutations that affect plaque morphology in phages (a and b ) have been isolated. Phages carrying both mutations (a b) are mixed with wild-type phages (a* b*) and added to a culture of bacterial cells. Once the phages have infected and lysed the bacteria, samples of the phage lysate are collected and cultured on plated bacteria. The following numbers of plaques are observed: Plaque phenotype Number a* b* 2043 a* b- 320 a b* 357 2134 What is the frequency of recombination between the a and b genes?A microbial geneticist isolates a new mutation in E. coliand wishes to map its chromosomal location. She usesinterrupted-mating experiments with Hfr strains andgeneralized-transduction experiments with phage P1.Explain why each technique, by itself, is insufficient foraccurate mapping.
- A researcher is studying the r// locus of phage T4. Three //-- strains are obtained: A, B, and C. E. coli strain K(A) is coinfected with two rl strains simultaneously and the results are recorded. Infection with A and B phage = lysis occurs Infection with A and C phage = lysis occurs Infection with B and C phage = no lysis occurs What can be inferred from this complementation test? Multiple Choice Strains A, B, and C have mutations in three different genes. Strains A and B have mutations in the same gene, and strain C has a mutation in a different gene. Strains A and C have mutations in the same gene, and strain B has a mutation in a different gene. Strains A, B, and C have mutations in the same gene. Strains B and C have mutations in the same gene, and strain A has a mutation in a different gene.By conducting conjugation experiments between Hfr and recipientstrains, Wollman and Jacob mapped the order of many bacterialgenes. Throughout the course of their studies, they identified severaldifferent Hfr strains in which the F-factor DNA had been integratedat different places along the bacterial chromosome. A sample oftheir experimental results is shown in the following table: A. E xplain how these results are consistent with the idea that thebacterial chromosome is circular.B. Draw a map of the bacterial chromosome that shows the orderof genes and the locations of the origins of transfer among thesedifferent Hfr strains.In E. coli, the gene bioD+ encodes an enzyme involved in biotin synthesis, and galK+ encodes an enzyme involved in galactose utilization. An E. coli strain that contained wild-type versions of both genes was infected with P1 phage, and then a P1 lysate was obtained. This lysate was used totransduce (infect) a strain that was bioD− and galK−. The cellswere plated on a medium containing galactose as the sole carbonsource for growth to select for transduction of the galK+ gene.This medium also was supplemented with biotin. The resultingcolonies were then restreaked on a medium that lacked biotin tosee if the bioD+ gene had been cotransduced. The following resultswere obtained:What topic in genetics does this question address?
- By conducting conjugation experiments between Hfr and recipientstrains, Wollman and Jacob mapped the order of many bacterialgenes. Throughout the course of their studies, they identified severaldifferent Hfr strains in which the F-factor DNA had been integratedat different places along the bacterial chromosome. A sample of theirexperimental results is shown in the following table:Analyze data. Compare and contrast. Make a drawing.In E. coli, the gene bioD+ encodes an enzyme involved in biotin synthesis, and galK+ encodes an enzyme involved in galactose utilization. An E. coli strain that contained wild-type versions of both genes was infected with P1 phage, and then a P1 lysate was obtained. This lysate was used totransduce (infect) a strain that was bioD− and galK−. The cellswere plated on a medium containing galactose as the sole carbonsource for growth to select for transduction of the galK+ gene.This medium also was supplemented with biotin. The resultingcolonies were then restreaked on a medium that lacked biotin tosee if the bioD+ gene had been cotransduced. The following resultswere obtained:What information do you know based onthe question and your understanding of the topic?The linear dsDNA genome of λ binds on the LamB receptor of E. Coli and conducts a normal lysogenic cycle. Exposure to stress will cause the excision of λ prophage from the E. Coli genome. The excised λ genome is then replicated, packaged, and released from the cell as mature λ phage particles and ready to infect other bacterial cells. Among λ phage particles,the transducing phage mediates a specific type of recombination. Understand this scenario and answer the following questions. 1. What are the basic requirements for the insertion of λ into the E. Coli genome? 2. What special features are found in the λ insertion site? 3. What type of recombination occurs with λ insertion in the E. Coli genome? 4. How you will differentiate λ transducing phage from normal λ phage? 5. What exclusive mechanism λ phage utilizes for recombination?